Navigation Links
Temperature, humidity affect health benefits of green tea powders
Date:5/18/2011

WEST LAFAYETTE, Ind. - The beneficial compounds in green tea powders aren't as stable as once thought, according to a Purdue University study that will give industry guidelines on how to better store those powders.

"People drink green tea for health benefits, so they want the catechins to be present," said Lisa Mauer, a professor of food science. "The instant powder beverages are becoming more popular for consumers, and it's important to know how storage can influence nutrition of your products."

Catechins are the source of antioxidants thought to fight heart disease, cancer, diabetes and other health problems. Green tea powders are often used as ingredients in products that are flavored like green tea or tout the health benefits of the tea. U.S. imports of green tea increased more than 600 percent from 1998 to 2007, according to the U.S. Department of Agriculture.

Mauer found that increased temperature ╨ and humidity, to a smaller degree ╨ speed catechin degradation. She said it had been believed that the powders were stable below the glass transition temperature, the temperature at which an amorphous solid changes from a rigid, glassy state to a rubbery, viscous state. In that rubbery state, compounds may start reacting with each other faster due to increased molecular mobility, leading to significant chemical degradation.

But Mauer's findings, reported in the early online version of the Journal of Agricultural and Food Chemistry, showed that green tea powder degrades at lower temperatures, even below the glass transition temperature.

"Tea powders are not infinitely stable below their glass transition temperature. They degrade more slowly below that temperature, but they can still degrade," Mauer said.

Catechin concentrations were tracked using high-performance liquid chromatography. The method involved dissolving the green tea powder into a solution, which then passed through a column. Compounds moved at different rates and could be measured.

More than 1,800 powder samples were stored at varying temperature and humidity combinations for up to 16 weeks and then measured for catechin loss. Those at the highest temperatures and humidities lost the most catechins.

From those results, models were built to predict the rates at which catechins would be lost at different storage conditions. Mauer said those in the food industry could use the models to predict the amount of catechins ╨ and the likely health benefits ╨ in green tea powder at the time it is used.

"Knowing what's happening to the ingredients is extremely important for understanding the quality of a food or beverage product," she said.

Mauer said she would next look at what the catechins become once they degrade and how those new compounds affect nutritional qualities.


'/>"/>

Contact: Brian Wallheimer
bwallhei@purdue.edu
765-496-2050
Purdue University
Source:Eurekalert

Related biology news :

1. Risk of beetle outbreaks rise, along with temperature, in the warming West
2. Humidity makes gecko feet stickier
3. New study looks to define evangelicals and how they affect polling
4. Vegetation hardly affected by extreme flood events
5. Scientist plans to test for blood pressure genes affected by age
6. Decline in Alaskan sea otters affects bald eagles diet
7. UC Riverside scientist to explore how vegetation affects urban heat islands
8. Seasonal affective disorder may be linked to genetic mutation, study suggests
9. Eliminating soda from school diets does not affect overall consumption
10. SNPs affect folate metabolism in study of Puerto-Rican adults
11. Previous abortions and exercise: Do they affect pregnancy?
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/31/2016)... , March 31, 2016  Genomics firm Nabsys ... founding CEO, Barrett Bready , M.D., who returned ... of the original technical leadership team, including Chief Technology ... of Product Development, Steve Nurnberg and Vice President of ... to the company. Dr. Bready served as ...
(Date:3/21/2016)... March 22, 2016 Unique ... passcodes for superior security   ... provider of secure digital communications services, today announced it ... and offer enterprise customers, particularly those in the Financial ... and voice authentication within a mobile app, alongside, and ...
(Date:3/14/2016)... March 14, 2016 NXTD ) ("NXT-ID" ... commerce market, announces the airing of a new series of ... week of March 21 st .  The commercials will air ... popular Squawk on the Street show. --> NXTD ... growing mobile commerce market, announces the airing of a new ...
Breaking Biology News(10 mins):
(Date:5/19/2016)... ... ... Anton Paar USA, located in Ashland, Virginia is pleased to announce that construction ... a third office building to the current facilities. , Growth is nothing new. ... with office space adjacent to the previous main building. Through remodels and new construction, ...
(Date:5/19/2016)... - I dati saranno presentati ... 52 ° Congresso della Società ... - Le conclusioni dello studio indicano un tasso di ... cui il 90% presenta una d urata della risposta ... settantadue per cento dei pazienti ha riscontrato un beneficio clinico. ...
(Date:5/18/2016)... ... May 18, 2016 , ... ... a direct result of asthma complications.* Costing more than $56 billion in direct ... , “For too many, the suffering associated with uncontrolled asthma can ...
(Date:5/17/2016)... Irvine, CA and Riyadh, Saudi Arabia (PRWEB) , ... ... ... Diagnostics Organization (CDO) for the biopharmaceutical industry, and BioSmartSA, a healthcare consultancy based ... the design and management of diagnostic services to healthcare providers in the Kingdom ...
Breaking Biology Technology: